IM-P15 4-11- US Issue 1 1
SDCV44 Split Disc Check Valves
1. Safety Information
2. General Description
3. Installation
4. Commissioning
5. Operation
6. Maintenance
© Copyright 2023
Printed in US
SDCV44
Split Disc Check Valves
Installation and Maintenance Instructions
IM-P15 4-11- US
Issue 1
IM-P15 4-11- US Issue 1
2
SDCV44 Split Disc Check Valves
Safe operation of these products can only be guaranteed if they are properly installed,
commissioned, used and maintained by qualified personnel in compliance with the operating
instructions. General installation and safety instructions for pipeline and plant construction,
as well as the proper use of tools and safety equip- ment must also be complied with.
1.1 Intended use
Referring to the Installation and Maintenance Instructions, name-plate and Technical
Information Sheet, check that the product is suitable for the intended use/application.
The products listed below comply with the requirements of the European Pressure Equipment
Directive 2014/68/EU and carry the mark when so required.
The products fall within the following Pressure Equipment Directive categories:
Product/Size Group 1
Gases
Group 2
Gases
Group 1
Liquids
Group 2
Liquids
SDCV44 – DN50
Class 150 / 300 N/A Cat I N/A SEP
SDCV44 – DN80
Class 150 / 300 N/A Cat I N/A SEP
SDCV44 – DN100
Class 150 / 300 N/A Cat I N/A SEP
i) The SDCV44 has been specificaly designed for use on Water, Hydrocarbon, and Heat
Transfer Oil. Which is in Group 1 Fluids of the Pressure Equipment Directive. SDCV44
can also be used on Steam or Air. The products use on other fluids may be possible but,
if this is contemplated, Spirax Sarco should be contacted to confirm the suitability of
the product for the application being considered.
ii) Check material suitability, pressure and temperature and their maximum and minimum
values. If the maximum operating limits of the product are lower than those of the system
in which it is being fitted, or if malfunction of the product could result in a dangerous
overpressure or overtem- perature occurrence, ensure a safety device is included in the
system to prevent such over-limit situations.
iii) Determine the correct installation situation and direction of fluid flow.
iv) Spirax Sarco products are not intended to withstand external stresses that may be
induced by any system to which they are fitted. It is the responsibility of the installer to
consider these stresses and take adequate precautions to minimise them.
v) Remove protection covers from all connections before installation.
1.2 Access
Ensure safe access and if necessary a safe working platform (suitably guarded) before
attempting to work on the product. Arrange suitable lifting gear if required.
1.3 Lighting
Ensure adequate lighting, particularly where detailed or intricate work is required.
1. Safety information
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SDCV44 Split Disc Check Valves
1.4 Hazardous liquids or gases in the pipeline
Consider what is in the pipeline or what may have been in the pipeline at some previous time.
Consider: flammable materials, substances hazard- ous to health, extremes of temperature.
1.5 Hazardous environment around the product
Consider: explosion risk areas, lack of oxygen (e.g. tanks, pits), dangerous gases, extremes
of temperature, hot surfaces, fire hazard (e.g. during welding), excessive noise, moving
machinery.
1.6 The system
Consider the effect on the complete system of the work proposed. Will any proposed action
(e.g. closing isolation valves, electrical isolation) put any other part of the system or any
personnel at risk?
Dangers might include isolation of vents or protective devices or the rendering ineffective
of controls or alarms. Ensure isolation valves are turned on and off in a gradual way to avoid
system shocks.
1.7 Pressure systems
Ensure that any pressure is isolated and safely vented to atmospheric pressure. Consider
double isolation (double block and bleed) and the lock- ing or labelling of closed valves. Do
not assume that the system has depressurised even when the pressure gauge indicates zero.
1.8 Temperature
Allow time for temperature to normalise after isolation to avoid danger of burns.
1.9 Tools and consumables
Before starting work ensure that you have suitable tools and/or consumables available. Use
only genuine Spirax Sarco replacement parts.
1.10 Protective clothing
Consider whether you and/or others in the vicinity require any protective clothing to protect
against the hazards of, for example, chemicals, high/ low temperature, radiation, noise,
falling objects, and dangers to eyes and face.
1.11 Permits to work
All work must be carried out or be supervised by a suitably competent person. Installation
and operating personnel should be trained in the correct use of the product according to
the Installation and Maintenance Instructions. Where a formal ‘permit to work’ system is in
force it must be complied with. Where there is no such system, it is recommended that a
responsible person should know what work is going on and, where necessary, arrange to
have an assistant whose primary responsibility is safety. Post ‘warning notices’ if necessary.
1.12 Handling
Manual handling of large and/or heavy products may present a risk of injury. Lifting, pushing,
pulling, carrying or supporting a load by bodily force can cause injury particularly to the
back. You are advised to assess the risks taking into account the task, the individual, the
load and the working environment and use the appropriate handling method depending on
the circumstances of the work being done.
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SDCV44 Split Disc Check Valves
1.13 Residual hazards
In normal use the external surface of the product may be very hot. If used at the maximum
permitted operating conditions the surface temperature of some products may reach
temperatures of 572°F (300°C). Many products are not self-draining. Take due care when
dismantling or removing the product from an installation (refer to ‘Maintenance instructions’).
1.14 Freezing
Provision must be made to protect products which are not self-draining against frost damage
in environments where they may be exposed to tem- peratures below freezing point.
1.15 Safety information - Product specific
See the relevant Section in the attached Installation and Maintenance Instructions for specific
details relating to this product.
1.16 Disposal
Unless otherwise stated in the Installation and Maintenance Instructions, this product is
recyclable and no ecological hazard is anticipated with its disposal providing due care is
taken.
1.17 Returning products
Customers and stockists are reminded that under Health, Safety and Environment Law, when
returning products to Spirax Sarco they must provide information on any hazards and the
precautions to be taken due to contamination residues or mechanical damage which may
present a health, safety or environmental risk. This information must be provided in writing
including Health and Safety data sheets relating to any substances identified as hazardous
or potentially hazardous.
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SDCV44 Split Disc Check Valves
2.1 Description
SDCV44 split disc check valves are of a wafer pattern, designed to be sandwiched between ANSI
150 or 300 flanges.
Their function is to prevent reverse flow on a wide variety of fluids.
The SDCV44 is designed for use with agressive fluids, vapours, acids and alkalines at high pressures
and temperatures.
The face-to-face dimension of the SDCV44 conforms to API 594. As standard the valves have a
metal-to-metal seat.
Note: For additional information see the following Technical Information Sheet: TI-P154-10-US.
2. General description
Fig. 1 SDCV disc check valve shown sandwiched between flanged connections
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SDCV44 Split Disc Check Valves
The product must not be used in this region.
A - BANSI 150 flanges
A - CANSI 300 flanges
Maximum body design condition
PMA Maximum allowable pressure 720 psi g (49.6 bar g)
TMA Maximum allowable temperature 650 °F (343.3 °C)
PMO Maximum operating pressure 720 psi g (49.6 bar g)
TMO Maximum metal seat operating temperature 650 °F (343.5 °C)
Minimum operating metal seat temperature -20 °F (-28.88 °C)
Designed for a maximum cold hydraulic test pressure 1475 psi g (101.7 bar g)
Note: Limited to flange rating
Temperature °F
Temperature °C
Pressure psi g
Pressure/temperature limits
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SDCV44 Split Disc Check Valves
Note: Before actioning any installation observe the ‘Safety information’ in Section 2.
Referring to the Installation and Maintenance Instructions, name-plate and Technical Information
Sheet, check that the product is suitable for the intended installation:
3.1 Check materials, pressure and temperature
and their maximum values. If the maximum
operating limit of the product is lower than that
of the system in which it is being fitted, ensure
that a safety device is included in the system to
prevent overpressurisation.
3.2 Determine the correct installation situation and
the direction of fluid flow.
3.3 Remove protective covers from all connections.
3.4 Before installing the SDCV remove the corrosion
inhibitor from the flange faces and clean the
machined faces on the disc and body seats using
paraffin or a similar liquid. This will remove the
last traces of protective coating.
3.5 Split disc check valves simply fit between two
pipe flanges (see Fig. 1). Standard gaskets are
used either side of the valve together with longer
bolts or studs.
Note: flanges, bolts (or studs), nuts and joint
gaskets are to be provided by the installer.
Normal sensible flange practice should be
followed e.g. torque tightening the bolts in
opposite sequence. Install the SDCV44 in the
pipeline checking that it has been fitted with the
flow in the direction of the arrow on the valve
body. If the valve is in a horizontal pipeline the
hinge pin must be in the vertical position for
correct operation. Split disc check valves can be
installed with the liquid/gas flowing horizontally
into the valve (Fig. 2 valve shown in the open
position), or with the liquid/gas flowing vertically
upwards through the valve (Fig. 3 valve shown in
the closed position). Split disc check valves are
not recommended for installation with the liquid/
gas flowing vertically down through the valve.
3.6 Split disc check valves are not suitable for use
where heavily pulsating flow exists, such as
close to a compressor.
3.7 Ensure suitable slinging/lifting/support
equipment and procedures are used relevant to
the valve size and weight.
3. Installation
Open Closed
Flow Flow
Open Closed
Flow Flow
Open
Flow
Closed
Flow
Fig. 2
Fig. 3
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SDCV44 Split Disc Check Valves
Before actioning any maintenance program observe the ‘Safety information’ in Section 2.
6.1 Before undertaking any maintenance on the valve it must be isolated from both the supply
line and return line and any pressure allowed to safely normalize to atmosphere. The valve
should then be allowed to cool. When reassembling, ensure that all joint faces are clean.
6.2 Remove the valve from the pipeline by loosening all flange nuts and removing sufficient
bolts or studs to allow the valve to be withdrawn from between the flanges. Note: Ensure
suitable slinging/lifting/support equipment and safety procedures are used relevant to the
valve size and weight.
6.3 Clean the valve removing any agressive media. Valves should be checked every 6 months.
6. Maintenance
After installation or maintenance ensure that the system is fully functional. Carry out tests on any
alarms or protective devices.
4. Commissioning
Disc check valves are opened by the pressure of the fluid and closed by the spring as soon as the
flow ceases and before the reverse flow occurs.
5. Operation
Spirax Sarco Applications Engineering Department
Toll Free at: 1-800-883-4411
SPIRAX SARCO, INC.
1150 NORTHPOINT BLVD.
BLYTHEWOOD, SC 29016
PHONE 803-714-2000
FAX 803-714-2222
www.spiraxsarco.com/global/us
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